Griggs returned to the States to plead for the creation of a national park to protect the Katmai area. This was a volcanic outburst, he argued, “such as the geologist finds recorded in the rocks of past ages but has never before had the opportunity to observe in the world of the present.” Katmai, he wrote, was an incomparable laboratory in which the effects of volcanism might be studied. There were so many natural phenomena of interest there, both to the general public and the scientist, that the area should be set aside.

On September 24, 1918, President Woodrow Wilson took time out from his conduct of the war to issue a presidential proclamation establishing the Katmai National Monument, in order to preserve “this wonderland … of popular scenic, as well as scientific, interest for generations to come.”